This invention relates to a simply-structured comb-shaped polarizing device which can polarize a laser beam.
In a laser oscillating apparatus, there is a case in which it is desired to polarize a laser beam.
Conventionally, for this purpose, for instance, a plane mirror inclined at a 45 degree angle was placed in a light path of a laser beam under oscillation and the laser beam was linearly polarized.
However, in a polarizing device by the above plane mirror, it is necessary that the placement be accurately adjusted so that the input light path to said plane mirror and the output light path from said plane mirror are not out of alignment, and thus it is difficult to design such an apparatus within a limited space and at low cost. Especially, in the case in which an attempt is made to design a laser oscillating apparatus compactly, since a light path is bent perpendicularly, the design becomes difficult.
Also, polarization by a plane mirror polarizes a laser beam in only one direction and thus, the direction of the polarization can not be adjusted.